SEP Integrated

steve f · « **on:** 2 Apr 2013, 10:17 pm »

What can be done in terms of a 20 WPC integrated? Any pictures of prior work? I've always ran separate preamp and amp. I tried a friends CJ integrated (cv-50?) and was completely unimpressed. Now I'm wondering about built in buffer or preamp stages etc. Comments please.
And how is the shop coming along?

Steve

Niteshade · « **Reply #1 on:** 3 Apr 2013, 06:08 pm »

Hello Steve-

Sorry I didn't see your letter earlier.

Here is an integrated SEP20 found on our web site:

This amplifier has a passive preamp built in that's similar to our stand-alone model. An active preamp modeled after the Beacon One can be installed as well.

What sound qualities would you prefer?

What is the sensitivity of your speakers?

_______________________________________ _________

This shop is unfinished at the moment. One of the original contractors has to make some repairs in the spring
because the foundation (pad) was screwed up by something. After that, a concrete floor is going to be installed instead of a wood plank model. Due to the INSANE quotes and people who do NOT know what they're doing, I have been learning how to do much of the work myself and a friend will help me this summer. We're about two months behind so far.

Teaching others how to work for me (the things I could do before) has been stressful and expensive, yet they do good work. Working out of boxes issues are nearly resolved and the in-house shop is much better now than it was a month ago.

steve f · « **Reply #2 on:** 4 Apr 2013, 08:35 pm »

Blair, You have my sympathy with the building. I am getting my house ready for sale and struggling with contractors too. And yes, I do as much as possible as I can myself. I don't want to but ...well you know.

As far as the amp goes, I want a unit for a second system that's simple to use, aka user friendly, for my music loving wife. I want an active preamp or buffer stage. I build speakers so they get changed out a couple of times per. I favor fairly high efficiency units; most are about 94-97 DB. Passive preamps suck IMO. An active line stage with 2 inputs is preferred. I'm also a big fan of highly regulated tubes, tight neutral, depth, and soundstage. I also hate tube rolling. That's my wish list.

Steve

Niteshade · « **Reply #3 on:** 5 Apr 2013, 12:10 am »

An active input is something I offer. There is absolutely NO performance compromise with the method I use to install them. You will receive the same performance as with separates. Some may consider it better because it reduces the amount of interconnects that are necessary to use.

When you say regulated tubes- are you referring to regulated voltages?

Tube rolling is not necessary when you begin with very good tubes. I know several good ones and will be happy to make a suggestion.

The SEP amplifiers are designed to provide a rich, natural output. The sound stage is forward and enveloping. Speakers within the 92db and up range are ideal for a 20W/ch SEP amplifier. One other facet that people like about these amps: They're extremely fluid, meaning continuity within complex and demanding passages is ideal.

I'll be happy to answer more questions about these amps.

opnly bafld · « **Reply #4 on:** 5 Apr 2013, 12:22 am »

Doesn't SEP refer to single ended pentode?
PSE is used for parallel single ended right?

Niteshade · « **Reply #5 on:** 5 Apr 2013, 08:59 am »

SEP stands for Single Ended Parallel with amps that use multiple output tubes in parallel with my products.

I never used the term PSE for these products. To me, it's better not to designate what kind of tube is being used and better to designate the output circuit architecture. I do not use the term SET even when triodes are the output tubes. It's better to designate a single ended amp as SE.

I can make solid state SE and SEP amplifiers too. There hasn't been enough time yet and I do have the parts necessary to build prototypes. Talk about fun!

steve f · « **Reply #6 on:** 8 Apr 2013, 08:10 pm »

I guess I'm just the guy who enjoys solid state rectification for tube amps. That's basically what I prefer. Too many tube amps sound soft to me, and I think it takes away from the harmonic richness tubes can provide. FWIW my preamp these days is a SS unit that has a choice of either 6DB or unity gain. I suspect a SEP-20 with a low gain preamp section in an integrated amp ( remote too?) would be just about perfect. The only other consideration would be a PP EL-84 same configuration. Power would be close enough between the two, just a different approach. I have never experienced an SEP amp so it's a bit more tempting right now.

I'm definitely not a SE Triode (I'm learning your terms) guy. They tend to sound syrupy to me, even when a pentode is used. I don't want to name brands, but I got rid of two popular units.

Sorry for a bit of a disconnect in this thread. I meant to reply sooner, but time got away from me.

Steve

Niteshade · « **Reply #7 on:** 9 Apr 2013, 11:31 pm »

Time gets away from all of us at times- including myself because there are so many things happening now.

What you're looking into is what I call a modern tube sound: Rich sound, high res, not bloated within any part of the spectrum. My SEP amplifiers are ideal for people who like the tube approach to high resolution without a hint of nostalgic tonality. Using solid state rectification enhances resolution by allowing the power supply to make a well regulated plate voltage. Less voltage sag equates to a purer spectrum as well as the ability to handle bass accurately.

Pentodes are excellent tubes for the output stage. Their internal components vs. a power triode promote improved efficiency as well as much more refined driver circuits.

I have not ventured into putting a remote control into an integrated amplifier and I will think about it.

Did you want an active preamp section in an amplifier? That would offer added gain and we can add a unity gain feature if you like.

FullRangeMan · « **Reply #8 on:** 10 Apr 2013, 12:49 am »

Would these solidstate gadgets apply to hi-fi amps??

http://www.amazon.com/Yellow-Jacket-Solid-Tube-Rectifier/dp/B0042AOHY4

steve f · « **Reply #9 on:** 10 Apr 2013, 10:00 pm »

I have to remind myself that the integrated amp is mostly for my wife's use, not mine. An active preamp section of 6+DB would work out well. A unity gain feature would be cool but not needed. In fact a buffer for matching up sources to the amp is probably the sensible choice. Two source inputs, and a balance control, or better yet mono pots are all we need.

You hit the nail on the head with "modern tube sound" amplification. That's my goal.
Plus hot rod red chassis and black carbide transformer caps.
steve

4krow · « **Reply #10 on:** 12 Apr 2013, 01:43 am »

Wow, those 'Yellow jackets' seem to be a good way to find a preference W/O a lot of trouble.

Niteshade · « **Reply #11 on:** 12 Apr 2013, 07:10 pm »

The plug-in rectifiers are interesting and will work with the way my amplifiers are biased. One option we presently have is switchable tube/solid state rectification. The tube rectifier can remain in the socket yet be bypassed to solid state rectifiers with the flip of a switch.

FullRangeMan · « **Reply #12 on:** 12 Apr 2013, 08:59 pm »

Quote from: Niteshade on 12 Apr 2013, 07:10 pm

The plug-in rectifiers are interesting and will work with the way my amplifiers are biased. One option we presently have is switchable tube/solid state rectification. The tube rectifier can remain in the socket yet be bypassed to solid state rectifiers with the flip of a switch.

This is my favorite system yet. It is as two amps in one.

Ericus Rex · « **Reply #13 on:** 12 Apr 2013, 11:34 pm »

Quote from: Niteshade on 12 Apr 2013, 07:10 pm

The plug-in rectifiers are interesting and will work with the way my amplifiers are biased. One option we presently have is switchable tube/solid state rectification. The tube rectifier can remain in the socket yet be bypassed to solid state rectifiers with the flip of a switch.

How would you describe the difference between the sound of the two?

steve f · « **Reply #14 on:** 13 Apr 2013, 01:06 am »

Blair, I've noticed that integrateds can have a buffer option. Could you elaborate a bit on that?

Steve

Niteshade · « **Reply #15 on:** 13 Apr 2013, 04:05 pm »

A single tube rectifier, such as a 5U4 in a 20 to 40 watt/channel amplifier will provide a different midrange and bass response than solid state rectifiers. In a nutshell, it's how more warmth can be achieved. Solid state rectifiers provide better voltage regulation. The tighter regulation increases bass response and does not allow the midrange frequencies to overshoot badd or treble frequencies. There is more to this- such as tube rectification with lower wattage amps (6V6,EL84 types) will not change the amp's linearity as much.

Quote from: Ericus Rex on 12 Apr 2013, 11:34 pm

How would you describe the difference between the sound of the two?

Niteshade · « **Reply #16 on:** 13 Apr 2013, 04:07 pm »

A buffer provides isolation between the input and output of an amplifier's main circuit without increasing gain. I can make an integrated amplifier or preamplifier with a buffer mode so that you can choose to either have a preamp's gain or no gain at all, yet maintain the isolation.

Quote from: steve f on 13 Apr 2013, 01:06 am

Blair, I've noticed that integrateds can have a buffer option. Could you elaborate a bit on that?

Steve

steve f · « **Reply #17 on:** 13 Apr 2013, 10:17 pm »

So the buffer takes a high impedance output from a device like a DVD or CD player for example, and provides a low impedance load for the power amp?? Basically a preamp without gain?? In either case based on the beacon one??

(For simplicity's sake, I would have to choose one or the other.)

Niteshade · « **Reply #18 on:** 14 Apr 2013, 03:43 pm »

A buffer works exactly like an active preamp in regards to being an interface between the amp and a source. You can consider my preamp or active buffer as an interface which is easier for the amp's first amplifier to look at. The impedance of the amp input, source output were never considered an issue since the amp has a 100K input, non reactive. My preamps have a 100K input as well.

Having isolation between amp input and source provides a way to eliminate signal attenuation because the buffer is designed with slightly (a very small amount) more gain than the amp's, even with a nearly zero gain output. It's kind of like this: If you were having difficulty lifting 200lbs and your spotter helped you by gently pulling the weights up with only a couple of pounds lift, it enabled you to put the weights back on the rack.

One recommendation: I can make the active input with a moderate amount of gain, about 50% of a standard preamp. Working with only moderate gain can be better than no gain or high gain depending on what you're doing or what you like.

steve f · « **Reply #19 on:** 14 Apr 2013, 05:56 pm »

Thank you Blair. I'm starting to get a really good idea of what I want/need.

Since we are both in the construction doldrums, I finally had some good news. In one day, the guys who built my open stairway railings and cabinet trim work, got in & out without any further input from me... And did a great job. That is darn near miraculous these days.

Steve