TNT-Audio Readers' Corner
Monthly section devoted to your letters, positive and negative feedback about everything related to Audio and HiFi.

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January 2003

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Main(s) problem(s)
Dear Lucio,
Congratulations for TNT's new look and ever growing interest. I have a question concerning power quality.
American magazines often refer to the advantages of power conditioners and similar devices. British mags also do it, but not so much. I've read a few French mags and I didn't saw reviews or ads on power conditioners. I can't read Italian or German, so I don't know what they say. Searching TNT-audio (English pages), I found only one article: Platinum Power PP-1 reviewed by Nels Ferré. Once again, an American product tested by an American user.

I never tried any such product because they're not available at local dealers, and because British and American models use different plugs and outlets. In my country (Portugal), mains plugs and sockets are similar to those used in France.

Another question: is there any problem in plugging CD players and amps to the same electric outlet? Or should one use a wall socket for the CD and another for the amp?
Would you please share your views on this subject with your readers?
Thank you and keep up the good work.
Nuno Vidal - E-mail:

Dear Nuno,
we're planning to test one or two "European spec'd" power conditioners in the next months.
You can do something to improve the quality of your mains supply: use special mains cables (TNT TTS, Merlino etc.), use anti-RFI IEC sockets and - whenever possible - use separate outlets to feed the CD player and the amplifier. If the outlets are connected in parallel one to the other, this trick is useless. You may need two different lines at home: one for heavier duties such us heater, air cond etc. and one for lights. Then connect the amp to the heavier duty line and the CD player to the other one.
Furthermore, installing anti-RFI filters on other electric appliances may help (fridge, air cond, electric grills, fans etc.).
If still in doubt, use a 1:1 mains transformer to supply your HiFi system.
Of course, I'm supposing your power supply lines are already equipped with a GOOD ground wire.
Hope this helped.
Lucio Cadeddu

Screening for Mains Cable
Dear Lucio
I have just discovered the TNT site and have been working my way through its content. I am now very keen to try some of the simpler DIY projects, but have a couple questions on screening that I have not seen answered so far in the letters (although I admit I have not read everything!)

  1. I understand why an earthed braid acts as a screen around a cable, but why should the screen be earthed at one end only (socket end in the case of the mains cable).
  2. Merlino and TTS mains leads: Many people use a primary mains lead from the wall socket to a distribution block and separate mains leads to each piece of equipment. If screened mains leads are used should the screen of the equipment leads be earthed in the distribution block (and hence connected to earth through the "internal" earth wire of the lead between wall socket and extension block)? Alternatively, should it be connected to the screen around the lead between extension block and wall socket?
    Intuitively this latter answer seems best, but I'm not sufficiently confident to decide. Which is best and why and why?
Thanks for a great site.
Best wishes
Don Fleet - E-mail:

Dear Don,
first question: the shield has to be connected at one end only so to make it act as an antenna: it captates interferences and brings them to the ground (sorry for the gross approx.).
Second question: the distribution block needs to be earthed, otherwise the "previous" shielding is useless. Use a piece of Merlino or TTS cable to connect the distribution block to the wall socket and connect its shield to the ground.
Lucio Cadeddu

Mapletree Stealth 5 Monoblocks
Do you (or TNT) have any plans to review Mapletree Audio's Stealth 5 Monoblocks? Cf.
I really liked your review of their Octal 6. Thanks, and keep them coming!
Torrey Whitman - E-mail:

Hello Torrey,
Thanks for the email. I very much enjoyed working with the Octal 6 kit. It was great fun to put together and it sounded even better than I expected. In fact, I purchased the Octal 6 kit from Mapletree after I was done with the evaluation.

TNT Audio does not currently have the Stealth 5 Monoblocs on the review schedule. I had a brief discussion with Dr. Peppard several months ago about them, but we have yet to make arrangements. Thanks for reminding me to get back in touch with Dr. Peppard.
It is possible we will review them in the future. Just keep watching!
Richard George

Further update on upgrade question
You may remember you kindly answered my question about my next upgrade in your 7th December 2002 letters page and as requested I can update you as follows.
After much debate I upgraded my power amp to the Naim NAP 140 and what a difference! For the first time since their demo I am hearing the Opera IIIs to the fullest extent. The dynamics are incredible and the music is sublime.
Many thanks. I have not yet tried the NACA 5 speaker cable but it is next on my list.

Once again TNT provides good solid, practical and effective advice, I cannot thank you enough. Finally, we eventually made the interconnect and my son is now using it in his system. It has much more "air" and naturalness than the £29 (45 Euro) Monster interconnect he was using before.
Kind regards,
P.S. Love the new look of the site!
Fergus Taylor - E-mail:

Dear Fergus,
glad to hear my advice worked. Actually there's a huge gap in terms of "drive" and "control" between the Naim NAP 90.3 and the NAP 140. Try those Naim cables and let me know,
Lucio Cadeddu

Speaker Stands
I am interested in buying your speaker stands. How can I accomplish this.
Joseph Daniels - E-mail:

Hi Joseph,
Would you like them with or without blood stains :-)
All kidding aside, they are Not For Sale. They are part of our absolutely FREE, DIY (do it yourself) designs that we offer on TNT-Audio. We have everything for the DIYer from equipment feet, to equipment and speaker stands, all the way up to electronics.

If you don't have any tools to build one of our designs, let me suggest teaming up with one of your friends that has some tools and both of you build yourselves some pretty cool stuff. If you don't know anybody with the proper tools, I'm sure one of your local woodworking shops or cabinet builders would be happy to build them for you (for a cost).

Consider building them yourself. Even if you bought the tools you needed for the project, chances are, your (overall) investment would still be less than a comparable sounding, commercially availible, speaker stands. Then, with the tools you just bought, you could then build the ever popular TNT Flexy-Rack or Geoffs new BFB speakers.
Best Regards,
Scott Faller

Low powered tube amp
Dear M. George,
First, I would like to thank you and all the crew for your wonderful website. Very exciting for people who love music. Have A happy 2003 Year.

I have in my listening room an Atoll AM100 with PR100 preamp, connected to rega IO+Jupiter and rega Planar3. And Davis MV707 (93dB). Well, I think it's a good begining. Having heard several amps by now, I recently realized that, in fact, I was no more listening to the music, but I was listening to the Hi Fi system. Awful! So I decided to take it all back from the begining.

I've built Voigt Pipes with adequate single driver (98dB)...(and my wife went crazy when she gave a look at the pyramids, 1,90m tall and aqua blue finish, but that' s another story :-). LA RÉVÉLATION: I still like my 3 ways Davis, but I'm falling in love with the single driver.

Now, I want to buy a tube amp (just imagine why?). A low powered one. I'm sure of my choice because I had the luck to listen to my pipes with some french amp called "l'onde", Class A , 5watt, triode, single ended, etc...But it costs a loooooot of money, even in Euros.

And Now Comes The Problem: I read your review about Decware SE 84, I read other reviews about this amp. Very exciting. Without searching very far on the web, I found another amp called PARAMOUR manufactured by Doc Bottlehead (2A3 tube, SE, class A, No feedback, etc...) . And today, I found another one: the nOhr SE 9. All of them match about the same price for me when you add the shipping. So, where is the truth ? If there's any... EL 34 ? 2A3 ? SV 83 ? 300 B? DOES GOD REALLY EXIST IN THIS WORLD OF PAIN ? Or shall I return to my old kitchen radio, you know, the red one I bought In the late 70', and forget about Hi-Fi?
[Désolé pour mon anglais approximatif]
Eric Lindenbaum - E-mail:

Dear M. Lindenbaum,
Thank you for the note. You have elected to dive into DIY Voight Pipe speakers and SET amps. I hope you enjoy them! I reviewed the SE84B a few years ago, and I just finished a review on the SE9, which should be published on TNT soon. I have not evaluated the Paramours, but I have had a chance to listen to them.
My overall impressions:

SE9 - This is an entry level, single-ended pentode with EL34s. It has the most power of this group. While it sounds very good for its price, it lacks the refinement of the other two. It would be a better choice than the other two if you had 88 to 91 dB speakers.

Paramours - Very sweet and musical, somewhat lush sounding. This is an inexpensive way into directly-heated triodes. Bass is good, but a touch soft (tube changes can improve this). Naturally, the mid-range is wonderful! They have an audible hum, especially on high efficiency speakers, but that doesn't detract from the music.

SE84C - The most detailed of the three with excellent imaging. It is also as musical as the Paramours, but with a drier presentation. At only 1.8wpc, it should work beautifully with your Voight pipes - on one condition: The driver impedance must not be any higher than 8ohm. If it is higher, then the SE84C will not work well.
Oh, and no, don't forget HiFi - it is too much fun!
Richard George

Fi X
Dear Sir,
I've just finished reading your review of the Fi X. I want to congratulate you for accurately capturing the essence of this fine amp. I own a FI super X. I am enamored with the sound. I use it with Avantgarde Unos. The combination is simply more "human" than others I have tried. I am pleased to see Don get some well deserved press. The Super X is built to an even higher standard than the regular X. You should give it a listen if you ever have a chance.
Kind Regards,
Where can I get the Z formers?
Chris Keating

Dear Chris,
Thanks very much for your kind words. I always hope someone gets something out of what I write!
As for the Zero Autoformers, you can locate them at the following website:

They are ridiculously expensive ($400 on up), and if you do not have an impedance mismatch, they aren't worth the money. However, if you DO have an impedance mismatch (or review lots of equipment and end up with mismatches galore) then they work very well! In fact, I'll be finishing a review on them next month.
Richard George

Earthing of hi-fi components
Thanks for the projects that TNT has, that are a great help and a great fun to make, without forgetting the good results achieved. If possible, it would be good to have a few more pictures or diagrams for the DIY that you have, and a best of list for your cables would be good, in order to see the best result that one could expect for the chosen cable... I have tried the TNT-TTS and the TNT Triple T, and I am very pleased with the results. Next fase will be the interconnects.

About the earthing... I have a AV amp ROTEL RSX 1055 and a DVD player SONY DVD-NS700, and they are but connect with the TNT-TTS, but these equipments don't have a earthing pole on the plugs. Should I make a earthing connection of the chassis of the equipments to the earth conductor of the Cables? Is this a important issue? Can a person feel the difference on the sound, caused by the earthing connection? If yes, what are the things that should be connected to the earth pole? (chassis, main power board, etc...).

These questions are just a doubt that I have, because some manufacturers use the earth cable and others don't...
Best regards

PS: I have tried the round head screws as speaker spikes and they work fine, the speaker is no longer rocking...
Manuel Pousada - E-mail:

Dear Manuel,
as already explaing on this Readers' Corner, there are HiFi compoents that don't need earthing as they are already of the "double insulation" kind. Using special poer cords with earth can be useless. Anyway, you can still use a special mains cord and connect the shield to the earth at the wall's plug end (like you did, I assume).
Of course, you need to have a correct earthing at home (earth pole in each wall socket and a REAL earth somewhere outside :-)).
I do not recommend earthing a component that has been designed to work WITHOUT earth.
As for our DIY articles, we will try to put more pics in the future :-) [but we are limited_bandwidth-nuts]
Lucio Cadeddu

Just thanks
Thanks for your site. I had great pleasure to read it, and lot of fun about the tweaking zone :-)))) I read some of the reviews and I must say that they are definitely more complete and seem more real that those on magazines (that get money from advertising). Go on this way.
It is really a pleasure and a lot of information. Thanks again
Luc Mazzella - E-mail:

Dear Luc,
just thanks a zillion for the appreciation!
Lucio Cadeddu

Spectro Acoustics
Hey, Scott,
I'm a fan of TNT and also a fan of the Spectro Acoustics amps. I have a 200r and a 217 preamp. I was wondering what you did to modify yours?
Adrian Keevil - NY - E-mail:

Hi Adrian,
Well, where do I start :-) here, I'll list everything that I can remember.

I'm sure there was a few other things that I did but I can't remember them right now. If you are thinking about tweaking your amp and preamp, changing the caps out is THE place to start. Most of the stuff I listed is a really easy DIY project.

If you are handy with a soldering iron, go for it. Do yourself a favor, make the electonics (caps, resistors and rectifiers) changeouts in small steps. This allows you to understand the sound of each little improvement. Be sure to allow enough time for breakin before you move to the next tweak. Second and more importantly, if you make a mistake and the amp begins to make noise, you know right where to look to correct the problem.

I have a Spectro 217 preamp (several actually). It's a nice little pre with a great phono stage. Consider changing out all of the caps. You should hear huge improvements. Also, consider increasing the power supply capacitance in the preamp too. If you can afford it, go for Black Gates.
In the small values typically in a pre, they shouldn't be too expensive. I can't remember if the 217 is an opamp based pre (I don't think so but check). If so, changing the opamp with a modern Analog Devices or Burr Brown will get you huge sonic improvements too.

Let me suggest a little lite reading before you delve into your mods. Some time back Dejan wrote a great article on power supply designs and mods. Give this a read, there is loads of great info in it.
Have fun tweaking :-)
Scott Faller

Active or Passive?
Dear TNT
I have a Conrad Johnson Premier 11A power amp. The spec says its sensitivity is about 0.9 volts for full gain. All my sources have output voltages of at least that much. I'm thinking of using a passive preamp (Audio Synthesis Passion).
The input impedance of the 11A is a good match for the preamp (according to Audio Synthesis' guidelines). The interconnect between the preamp and the power amp will be less than 1 metre.
Given these facts, plus the common sense reasoning that putting the signal through an unnecessary gain stage can only degrade it and not improve it, is there any earthly reason why I should want to use an active preamp instead?
If you agree, are there any other quality passive controllers that I should consider besides the Passion?
Keep up the great work. What you are doing is the best example of what the internet should be all about.
Ian Reid - E-mail:

Dear Ian,
roughly speaking, I'm no big fan of passive preamps. Even if electrically compatible (sensivity and impedance match), in my opinion, a good active preamp sounds better and, last but not least, it can survive in your chain even if you decide to use a different power amp.
My suggestion is to search for a Conrad Johnson active preamp. If you like the CJ-sound you can't go wrong. Possibly, search for a second-hand top-of-the-line model.
Anyway, a good survey on pros and cons of passive preamps can be found in the article that explains how to build our own DIY passive preamp The TNT Pressive.
Also, for further infos, please read our review of a very high quality volume control, which can be used as a passive preamp, the Au/Ra D7A
Hope this helped,
Lucio Cadeddu

Mr. Husband,
Hi my name is Michael Pelley and I am writing to you from St. john's Newfoundland. I have just read your TNT BFB article and I must say I am very intrigued. I have never heard of a "full range" driver before and I was wondering if you could answer a few questions for me.....

  1. Do you have any pictures of the speakers you made(could give me some starting ideas)
  2. Can you use more than one driver per box (or would you want to)
  3. I currently have a pair of Mirage 390is floor standing speakers (one six inch driver and a soft dome) will these (if done right) be better then what I have
  4. Can you recommend any other full range drivers that might be better than the Fostex or do you think these are the best for the money
  5. What are the pros and cons of the full range driver (if they are so good why don't more companies use them)
Thank You for your time and I look forward to your response
Michael Pelley - E-mail:

Thanks for the mail I'll have a go at your questions...

  1. Lucio said if I didn't put a pic on I'd get emails :-) No I haven't, it's just a 45 ltr box, easy to work out, but you're free to try different shapes, the one I used was hardly perfect.
  2. You could but though you'd gain power handling and SPL's (though the BFB will produce 100 dbl+ with ease) you'd loose the "point source". If your room is huge then try two, but make one fire upwards, this would reduce the 'sting' as it's 'beamed' treble would be lost. Personally I'd build the basic BFB, if you then want to build a horn or double drivers you can later...
  3. The Mirage will be much more even, more extended at the frequency extremes. The BFB will go louder, be more dynamic and might well image better, it'll also be faster especially in the bass - they will sound VERY different...
  4. No I think the Fostex have it, if you have $300+ to play with then there are lots of alternatives, Lowther, Fertin, AER, Solavox, Fostex etc...
  5. Really covered in 1) as for why other companies won't use them... Lots of reasons:
Expensive (just work out how much the drivers are in typical a $1000 speaker, most are around $50)

Look "old fashioned".

Poor perceived value, punters buy by the number of drive units, selling a $1000+ speaker with one driver is difficult, just look at the number of cruddy drivers is a typical commercial speaker.

Poor measured performance - manufacturers don't like this. It looks bad in magazine group tests, and in a demo with a few commercial speakers they will sound "odd". However the ear will adjust. One problem is that when the BFB plays a crash cymbal you will wince.
A conventional speaker doesn't do that. However if you go to a music shop and slap one of their crash cymbals you'll wince :-)
Ditto a clarinet pointed at you and played hard will slice your ear drums, the BFB, because of their dynamics will do that, commercial speakers generally don't. In a way you need to re-educate your ears.

"Different" sound. They won't sound like your typical commercial speaker (all of which aim for a flat frequency response)

"How do they sound musically what other speakers would you compare them to in the high end world?"

In their strong areas they will thrash many high end speakers, in their weak areas they will be beaten by a decent $500 speaker.
My advice is build them! You may never look back.
Geoff Husband

Power caps tweaks
I am the (pretty) happy owner of the only HT receiver (Arcam AVR100) reviewed on your site. Actually, your review was what lead me to find TNT about a year ago. As cruddy as most of the HT stuff is it kind of lead me to hifi through the back door :-). Since then I've made some power cords and interconnects with favorable results. You guys got me started tinkering and I can't thank you enough.
Here's the question. In your review you mention that the supply caps in my amp are small and that it may run out of steam with really demanding electronic music. This does occasionally happen and I can't help but wondering if I should change the caps. Is this possible? Is it over my head? Any suggestions would be greatly appreciated.


Thanks for your time! Now it's back to work. Jon Banz

Hi John,
Glad to see that you found your way into our site :-) We've got lots of great DIY projects and tweaks that can really improve the sound of your system.

When it comes to your caps in the AVR-100, first let me remind you that you may be voiding your warranty. If I remember correctly, the Arcam comes with a two year warranty. If your warranty has run out, then it becomes fair game :-)

Absolutely, you can replace the caps. Unfortunately I can't remember what the values are in the unit. Considering Arcam rates this amp at 90wpc at 8 ohms, I'd say that your replacement caps should be no less than 15k-20k uF per channel. Remembering that you have a limited amount of space inside the amp, you will probably have to use the "Snap In" or compact style caps.
Pretty much anything from the "Con Brothers" (any company whose name ends with CON, ie; NichiCON, United ChemiCON, RubyCON, etc (Oh, Panasonics are OK too)) will work just fine. Just make sure that you at LEAST equal the voltage rating of the existing caps. The Arcams caps should be rated at 65 or 75 volts. Anything of a greater voltage is just fine.
Here, give a read to the three part article that Dejan wrote some time back.
A lot of what he covers in this article will apply directly to what you are planning on doing. It's a nice easy read with lots of pictures and schematics that will help in your understanding.

The final Caveat, BE CAREFUL, you are working with potentially lethal voltage and current. Make sure the unit is unplugged and the caps have discharged completely before you stick you hands inside the unit.

If you don't want to change the caps yourself, your local tech shouldn't charge you too much. It can't be more than an hour or so worth of labor.
Be sure to let us know how it turns out. Have fun tweaking :-)
Scott Faller

Triangle Titus amp matching
what budget integrated amp would you suggest for the Triangle Titus? What characteristics would best suit? Also, I am looking at the nad 521i as my cdp. Is this refined enough for the Titus? I want to create a system on a budget that gives me realism, transparency, and musicality at both low and high volumes for a 10x10 room.
With the low level resolution of the Titus and the small room, power is secondary to sound.
Thanks for your help and your excellent reviews.
PS - I also plan on using your audio rack, cd press, and vibrapods. Jim Petersen - E-mail: Jim.Petersen@WellsFargo.COM

Dear Jim,
considering the "lively" tonal balance of the Triangle Titus I'd suggest a NAD integrated amp, just choose the one that suits your budget needs (C300, C320 or higher). Considering this advice re: amp, the choice of a NAD CD player is simply the icing on the cake. Keep us updated on your findings abount our TNT FleXy rack and other accessories.
Lucio Cadeddu

AH! Njoe Tjube
Hi Scott...
thanks for your very informative and thorough review. Combined with the almost fanatical consumer reviews on, I'm seriously considering purchasing an Ah! for myself.
I'm also considering a Rotel 961 because of the HDCD capability. I noticed that your Arcam that was compared to the Ah! also has HDCD. Here's my question: is the Ah!'s sound even superior to the HDCD sound?
Thanks in advance.. and happy new year!
Andrew Linsk - E-mail:

Hi Andrew,
First, thanks for the praise :-) It's always nice to find that people appreciate our efforts. To answer your question, Yes, the Ah! sounded better when I was playing HDCD's in the Arcam and the same CD in the Ah!.
Now, hold tight a bit. Along with the Ah!, Herman is offering an 24/192 Upsampler. I have one here for review. To put it simply, it kicks butt, BIG time.
This thing takes longer to break in than any piece I've ever had (almost 500 hours on it so far) but when it does, this thing is fabulous. It's relatively cheap too, $299 USD. I'm still playing with it, changing tubes and waiting for it to finish breaking in but I'll tell you this on the QT, it has completely transformed the sound of this player. It's in an entirely new league now.
Keep a watch out for the formal review. Best guess, about 4 weeks from now.
Happy Hunting,
Scott Faller

About them Stoneblock clones
Great website.
I tried your StoneBlocks tweak under our DVD player (on which I also playback CDs) and found the overall sound to be much improved. Great trick.
I did however modify them somewhat by wrapping one set in electrical tape and another in duct tape. This didn't seem to effect the sound improvement but made handling the blocks easier. I am going to experiment some more but I thought you might like to know about wrapping these things up.
Many thanks
Best Regards
Paul Laplante - E-mail:

Dear Paul,
I have no objection to wrapping the StoneBlocks. This actually makes them easier to handle. Do not expect big changes in overall sound, though.
You can try a combination of spikes and StoneBlocks, as well.
Keep us updated, your feedback is always welcomed!
Lucio Cadeddu

OpAmp upgrade
Hi Lucio,
I was reading the Reader's Corner and I decided to e-mail all you nice people who read THE BEST audio-related site I know: TNT-AUDIO.
The reason for this mail is for all of you who still own an Audio Alquemy DDE v3.0 Dac (or am I alone?) :-).
Just unsonder and get off those OP-176 Op-Amps, put new machined sockets and Burr-Brown OPA627 Op-Amps. Then you'll be a happy man, as I am, when I listen to music.
I did't noticed before the incredible resonances Ben Harper's guitar makes when he's playing...
Well Lucio, keep on with the good work, and see you on the next Tweak!
Carlos Filipe Machado - E-mail:

Dear Carlos,
thanks for the the useful tip. Audio Alchemy DDE's are damn cheap nowadays so they're an absolute bargain. Try adding a good DIY mains cable, as well, and let us know what you think.
Lucio Cadeddu

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