new products for 2012

start saving your Christmas cash for these new products coming next month . . .
http://www.tubes4hifi.com/new12.htm

* SP14 preamp - similar circuit as the SP12 but using all octal tubes and all dual mono,
including dual mono regulated tube power supplies

* PH14 phono preamp - similar circuit as the PH12 phono preamp but includes dual mono regulated tube power supply
and tube buffered output, perfect RIAA EQ from 10Hz to 40KHz within 0.1db, 45db gain for MM and 53db gain for MC

* HA12 headphone preamp - all tube headphone amp, using 2 12AX7 tubes, 2 EL84 tubes, and 6CA4 hi-voltage rectifier tube.

* HA6 headphone preamp - use 12AU7 or 6922 tube for voltage gain, MOSFET current buffer for output

* M70 monoblock amp with OCTAL drive uses two 6SN7 tubes, two KT88 tubes (for 70 watt output) and EZ81 hi-voltage rectifier tube

The
M70 and the Octal preamp sounds real cool.

Merry Christmas!

.

The PH14 sounds great.

I hope it will include tone controls for these old ears and two outputs per channel (one of which is variable) and maybe even selectable capacitance and resistance for mm and mc cartridges, respectively?

Falcon4646 wrote:The PH14 sounds great.

I hope it will include tone controls for these old ears and two outputs per channel (one of which is variable) and maybe even selectable capacitance and resistance for mm and mc cartridges, respectively?

I like the way you think Falcon4646. I really enjoy my SP9 preamp with the PH6 phono stage, if the SP14 and PH14 sound even better (no doubt they will!) , I'd be in vinyl heaven!

from the last two it seems maybe you want an octal version of the SP9, it's available now . . . . .
email or PM me to order as it's not listed for sale on my website yet . . . .

more new photos added here: www.tubes4hifi.com/new12.htm

got an email from "TMadden" this morning, reporting back on his new PH14 phono board . . . .

"Holy Crap Roy!
The PH14 sounds freakin’ awesome! First thing when I got home from work this morning I soldered up the PH14 board and put it my preamp. Damn the thing is so dynamic and open and punchy sounding , wow! Smooooth and clean! You just want to crank it! I wish I had megabuck pre here to compare it to. Anyway I think you have a real winner there!"

Hey TMad',

Congratulations on pulling the trigger on this one. I'd been resisting the urge to get an SP12, but when Roy announced the upgrade, all resistance was futile!

By the way, are those M125 monoblocks in your avatar? How do you like em?

Yes, those are the M125's! I really enjoy them, they are in my main system, I listen to them every day. Very natural, smooth, easy on the ears!

from the last two it seems maybe you want an octal version of the SP9, that can be done in a few weeks . . . . . tubes4hifi

No -- what I would like is a ph14 with ±10db tone controls and maybe a switch for going flat (and guaranteeing it). A major reason for going with a high performance preamp as a separate piece of gear is to have it be capable of providing all the control and switching function one would need. One should not have to compromise the electronics to get tone controls or invest in a separate transistorized graphic equalizer that adds its limitations plus acts on the signal after the preamp. One still needs to compensate for old ears, room acoustics, and source material.

Still looking for something affordable, I can build, to go with my VTA M-125s.

Falcon,
while my power and internet were down for a few days, I did some deep thinking and consulting with another tube audio engineer,
and we both concluded that a "simple" tone control for a tube "hi-fi" product will never work correctly
(they are common in tube amplifiers where accurate frequency response isn't important at all).
Amplitude variation using the simple circuit is as much as 6db from being correct, and the controls are interactive,
and change the input loading and output impedance with any change in tone setting.

The solution is the marriage of the PH14 phono pre with the last 3/4 of the "TCLA" circuit (the basis of the SP9 preamp).
The TCLA circuit uses active equalization and linear tone pots, versus passive EQ and log taper pots for a "simple" design.
This will give absolutely perfectly flat response at midpoint, and adjustment of about +/- 10-12db for bass and treble.
Both boards are small and can be powered from the same power supply, and even fit in a small chassis.
7 tubes total with the tube rectifier. Send me a PM or email if you're interested.

I'm certainly not the expert that Roy is but I'll throw in my 2 cent's worth since I have the SP9 preamp with a built in PH14 phono stage in my current system. The SP9 TCLA line stage has for me effortlessly conveyed the sound quality differences of various 12AX7 tubes, several different phono stages, every LP I have played, and now the very different character of a fine moving coil cartridge vs a very good moving magnet cartridge. It also sounds fantastic with my Marantz CD deck. To my ears it is a very transparent, pleasing line stage. Soon I will be able to compare it to the SP14 line stage, the kit is on the way! If I understand Roy's post he is proposing eliminating a redundant stage in the SP9/PH14 combo to attain even better performance. I would be interested in that as well, as I too enjoy having tone controls, even if they do impose some slight sonic penalty. Actually I may have already done something similar to what Roy is proposing, as I have experimented with bypassing the final stage of the PH14, reasoning that it is mainly there to drive a seperate line stage and the associated cables. Hard to tell if there is much of a difference, as I can't compare directly. It certainly did not seem to hurt the sound! Also, it seems to me I could get about the same result using the PH12 phono stage , is that correct Roy? Also Roy, can I simply add a DPDT switch to bypass the TCLA tone control unit? (Hmmm, come to think of it, I don't use the tape monitor switch)

I see that part of the topic is on tone controls. What is interesting to me is hearing a recording in the way the final mix was cut for the finished product. Having a VTA ST 70 is a joy to listen to as it is so dynamic. It makes the music more enjoyable to listen to. That said, being a purist, yeah a little more bass or a little more treble might spice things up abit, but I prefer to listen to what the musicians and producer intended for us to hear. So I'm not for tone controls.

the main difference between the PH12 and the PH14 is an output buffer stage, used to isolate the load from the phono EQ and thus give slightly better (flatter) EQ. What I proposed to Falcon is the TCLA stage without the first gain stage (the 20db used as a line preamp), thus leaving the buffered tone EQ stage and output gain to make up for the tone EQ 20db loss. So yes, the PH12 could also be used with the latter 3/4 of the TCLA circuit to have a phono only tone controlled preamp. The output would be quite a bit lower than that of a phono stage-line stage combination, but for someone using only a phono input and no other sources, directly into an amp with decent gain (hi-gain version of VTA70) it would be a good solution.

due to popular request, the following new products are being added:
octal version of SP9 preamp, available now! uses 4 6SL7 tubes and 6X5GT rectifier

octal version of VTA70 & VTA120 driver board, with CCS on the phase splitter, uses 3 6SN7
or you can use 6SL7 in center position for more gain - ready to go anytime!
VTA70-octal $49 PCB, $99 kit with parts.

and, a preamp for the budget minded, a simplified version of the SP8 (same exact circuit without phono),
line stage and power supply combo, in a small chassis (12"x8" or even 10"x6")
(that alone knocks over $100 off the price of my other preamps),
so I can finally offer a COMPLETE preamp kit with custom chassis for under $450 that will blow everything else away.
Basic PCB kit with parts $99, just add a transformer and chassis (buy a PAT4 for $50!!) and you're done!
This is the new SP8-Z model, and the PH6 phono circuit can be added to it anytime using same power supply.
Once I get caught up on SP14 orders, I'll build a sample and take photos and get it listed for sale.